1. Field of the Invention
This invention relates to a method of determining a threshold value for gaining access to a communications network and in particular, but in no way limited to the case where the threshold value is a price. The invention also relates to an apparatus for implementing this method and to a communications network comprising such an apparatus. The invention also encompasses a computer program for controlling the aforementioned apparatus.
2. Description of the Prior Art
Traffic levels in a communications network typically vary over time and one problem for network operators is how to make maximum use of the network resources such as bandwidth despite this variation. However, at the same time, network operators need to ensure that the performance of network resources does not drop because of over-use. For example, when there is over-use of communications network resources such as the switching capacity of routers, the bandwidth of the transport medium, and the disk and CPU capacity of popular servers, then performance of these resources drops dramatically and affects the overall performance of the network.
One approach to dealing with communications network resource allocation is to establish rationing or quota systems. Under these types of schemes, additional users are simply rejected by web servers or other network services when the load becomes too high. One advantage of rationing and quota systems is that they are simple. However, under this type of system the relative values that users place on use of the communications network are not taken into account and whether a particular request for a communications session is accepted or rejected under such a scheme is arbitrary.
An alternative approach involves using pricing mechanisms to deal with resource allocation in communications networks. This type of approach has been analysed theoretically by economists such as MacKie-Mason and Varian in, xe2x80x9cPricing congestible network resourcesxe2x80x9d, IEEE Journal on Selected Areas in Communications, Vol 13. No. 7 September 1995. However, until now, no practical implementation of such a pricing mechanism has been proposed for a communications network. The theoretical pricing mechanism methods rely on providing customers with a price that varies depending on particular factors. Providing such a price allows the customer to weigh up their own costs and benefits from usage and the congestion cost that they will impose on other users. However, no practical way of providing such pricing information to users has been proposed. One particular problem involves providing pricing information to customers quickly, in order that the prices are not xe2x80x9cout of datexe2x80x9d when they reach the customer. Another problem involves providing pricing information without creating large amounts of additional traffic as a result of the pricing mechanism itself. As well as this the price needs to reflect factors to do with a whole route over a communications network which comprises a plurality of nodes and links. One problem is how to provide a single xe2x80x9cpricexe2x80x9d which reflects factors over a whole route rather than just a localised region of a communications network.
It is accordingly an object of the present invention to provide a method of determining a threshold value for gaining access to a communications network which overcomes or at least mitigates one or more of the problems noted above.
According to the present invention there is provided a method of determining a threshold value for gaining access to a communications network, said communications network comprising a plurality of resources, said method comprising the steps of:
for each of a plurality of the resources determining a first value on the basis of the amount of resources available at that resource; and
determining said threshold value on the basis of one or more of said first values.
This provides the advantage that a threshold value is given which enables a customer to weigh up their own costs and benefits of using the communications network at a particular time, as well as enabling the customer to take into account the effect that their own use of the network at that time will have on other users. The threshold value is a single value that is simple and used to represent complex information in a straight forward manner.
The present invention also provides a method of controlling access to a communications network said communications network comprising a plurality of resources, said method comprising the steps of:
receiving an access request from a user, said access request containing a first value;
for each of a plurality of said resources, determining a second value on the basis of the amount of resources available at that resource;
determining a threshold value on the basis of one or more of said second values; and
comparing said first value and said threshold value and allowing access to said communications network on the basis of said comparison.
This provides the advantage that a service provider or network operator is able to control access to a communications network in a way which promotes efficient use of the communications network and tends to prevent congestion. The method of controlling access to the communications network is simple and quick to operate.
The present invention also provides a method of requesting access to a communications network, said communications network comprising a plurality of resources, said method comprising the steps of:
sending a request for a threshold value to a node in said communications network;
receiving said threshold value;
sending a request for access to said communications network said request comprising a value determined on the basis of said threshold value.
This enables a customer to request access to a communication network in such a way that the communications network resources are efficiently used. The customer is able to take into account his or her own costs and benefits of using the network as well as the effect that the proposed use will have on other users of the network. At the same time, the method for use by the customer is simple to understand and operate.
According to another aspect of the present invention there is provided an apparatus for determining a threshold value for gaining access to a communications network, said communications network comprising a plurality of resources, said apparatus comprising:
an input arranged to access a first value related to the amount of resources available at that resource, for each of a plurality of said resources;
a processor arranged to determine said threshold value on the basis of one or more of said first values.
This provides the advantage that equipment for determining the threshold value described above is given.
According to another aspect of the present invention there is provided a communications network comprising a plurality of resources and a processor arranged to access a plurality of first values, each related to the amount of resources available at a resource, and wherein said processor is arranged to determine a threshold value on the basis of one or more of said first values. This provides the advantage that a communications network which comprises equipment for determining a threshold value as described above is given. All the advantages provided by this threshold value as then attained as described herein.
According to another aspect of the present invention there is provided a computer program stored on a computer readable medium, said computer program being arranged to control an apparatus for determining a threshold value for gaining access to a communications network, said communications network comprising a plurality of resources, said computer program being arranged to control said apparatus such that:
a plurality of first values are accessed, each relating to the amount of resources available at one of said resources; and
a threshold value is determined on the basis of one or more of said first values.